d iv 


f 1868 


1886.  ? 


JRON  piGHWAY  ^RIDGES, 


AS  BUILT  BY  THE 


E’EN^^ 

] 

Rridge 

@PANY, 

b:e]-z^’\7’e:ee  zf^XjLS. 


^c. 


Eastern  A^ent, 

.T«  TltlBUSE  BUILDIMi,  | 

NEW  YORK.  A 

- ■ 


Digitized  bS^‘^tHid“ffrtirnet  Archive 
in  2017  with  funding  from 
Columbia  University  Libraries 


https://archive.org/details/ironhighwaybridgOOpenn 


The  Penn  Bridge  Company 


locviver-  lYM.'y,  l'’;i 


ENGINEERS  AND  MANUFACTURERS, 


CONTRACT  FOR 


Wrought 


Jr^on,  Steel  and  Pombination  Bridges, 

IRON  SUB-STRUCTURES, 


Building’S,  Roof  JTrusses,  Plate,  Box^and  Lattice  Girders, 


Architectural  Iron  Work  Generally, 


To  The  Public. 


TT7E  wish  to  extend  our  tliauks  to  our  friends  and  patrons  for  the  cordial  welcome  which  was  extended  to  the  first  editi<m  of 
¥ T our  illustrated  pamphlet.  Some  additional  illustrations  have  been  added  in  this  edition,  which  will,  we  trust,  make  it  of 
/ still  more  interest  to  you.  We  wish  to  add  something  to  the  general  fund  of  information  possessed  lyv  those  who  have 
charge  of  the  letting  of  Bridge  Contracts,  and  to  aid  them  in  instituting  a fair  comparison  between  different  j)lans  submitted,  so 
that  those  which  have  the  greatest  merit,  if  presented  by  a Company  having  a good  reputation  for  fair  dealing  and  good,  honest 
work,  may  have  the  preference  to  which  they  should  he  entitled.  We  make  no  claim  that  we  are  the  only  Ifridge  Company  that 
can  or  does  do  good  work ; but  we  feel  confident  that  our  many  patrons  will  bear  us  out  in  the  statement  that  we  always  en- 
deavor to  faithfully  perform  our  contracts,  and  to  keep  in  the  front  in  the  march  of  improvement.  Few  persons  realize  how  vast 
has  been  the  imiu'ovement  in  Iron  Bridge  construction;  how  much  of  it  has  been  accomplished  within  a comj)aratively  short 
period,  and  how  long  is  the  list  of  names  of  the  pioneers  and  promoters  of  this  great  industry.  Ft  may  not  be  amiss,  in  this  con- 
nection, to  append  a brief  sketch,  giving  a few  points,  some  of  which  may  be  new  to  our  readers. 

IRON  BRIDGE  CONSTRUCTION. 

The  earliest  bridge,  in  the  construction  of  which  iron  formed  the  principal  part,  was,  if  we  may  believe  Kirchen,  in  his 
“China  Illustrated,”  a product  of  the  civilization  of  the  great  Oriental  Empire  in  the  days  of  anticpiity,  prior  to  the  Christian 
Era,  in  the  form  of  a Suspension  Bridge  composed  of  chains,  on  which  the  floor  was  directly  laid,  following,  consequently,  the 
curvature  of  the  suspended  chains. 


c 


ri’:-  r 


We  liave  no  further  record  of  tlie  use  of  iron  in  bridge  construction  until  a long  time  afterward,  about  the  close  of  the  last 
I century,  when  cast  iron  was  employed,  instead  of  stone,  in  the  construction  of  an  arch  bridge  of  one  hundred  feet  span,  at  Cole- 
brookdale,  England.  It  has,  however,  remained  for  the  present  century  to  develop  the  highly  perfected  forms  of  wrought  iron 
and  steel  bridges  which  we  now  have.  Of  these,  the  enormously  heavy  tubular  bridges  across  Menai  Strait  and  the  St.  Lawrence 
are  amongst  the  principal  precursors,  on  the  one  hand  as  to  the  material,  and  the  simple  skeleton  structures  of  Whi|)ple,  on  the 
other  hand  as  to  the  tyj)e,  to  which  the  more  elastic  and  trustworthy  material  has  been  adapted,  replacing  tbe  crude  unreliable 
cast  iron  which  so  largely  entered  into  the  earlier  bridges  of  this  form.  Post,  Fink,  Warren,  Bollman  and  others  introduced 
various  forms  of  skeleton  structures  as  distinguished  from  the  solid  tubular  girders  and  heavy  lattice  trusses;  and  these  all  have 
been  modified  in  form  and  improved  on  in  details  by  Latrobe,  Murphy,  Linville,  C.  Shaler  Smith,  Cofrode,  Wilson-,  and  like  in- 
genious men;  while  Wood,  Shreve,  Merriman  and  Burr,  have,  through  complete  and  elaborate  investigations,  jdaced  such  form- 
ulas in  the  hands  of  the  engineer  as  to  enable  him  to  disj^ense  with  much  of  the  drudgery  and  tedious  courses  of  experiments  on 
models,  etc.,  which  the  earlier  builders  had  to  go  through  with,  and  to  entirely  do  away  with  the  “rule  of  thundi”  methods 
which  were  much  in  vogue  among  a certain  class  of  highway  bridge  builders  some  fifteen  or  twenty  years  ago.  We  have  said 
nothing  of  the  development  of  suspension  bridges  by  Ellet  and  the  illustrious  Rmfiding,  which  has  its  greatest  achievement  in 
the  Brooklyn  Bridge;  as  it  is  a peculiar  and  special  type  which  has  been  shown  to  be  only  desirable  in  such  long  spans  as  are  as 
yet  unusual  in  framed  structures.  A good  illustration  of  this  type,  as  designed  and  built  by  our  Mr.  Shipman,  is  however,  shown 
on  page  24.  The  Niagara  Cantilever  Bridge  bids  fair  to  be  the  forerunner  of  a formidable  competitor  to  suspension  bridges  for 
long  spans.  Our  wish  is  now,  however,  to  trace  out  simply  the  development  of  that  class  of  bridges  winch  is  a universal  want 
of  the  civilized  world  for  the  common  roads  and  highways  of  the  people.  Among  the  first  iron  highway  bridges  in  this  country 
were  the  cast  iron  bow-string,  commonly  called  arch,  truss  bridges,  built  by  Whipple  in  eastern  and  central  New  York.  The 
arches  were  cast  in  straight  segments  of  a circle,  increasing  in  width  from  the  center  or  top  of  the  arch,  to  the  skewback  or  base ; 
they  were  very  heavy,  thereby  making  a well-braced,  solid  structure ; the  lower  chord,  or  string  of  the  bow,  was  made  of  long 
links  of  round  iron  formed  just  as  the  links  of  a chain  are  made,  but  of  lengths  equal  to  that  of  the  panels  of  the  bridge ; these 
were  connected  by  oval  shaped  cast  iron  bars  or  pins.  Mr.  Whipple  also  built  a number  of  truss  bridges  of  the  type  known  by 
his  name,  with  cast  iron  upper  chord  and  posts.  These  bridges,  however,  were  expensive,  and  in  the  country  west  of  New  York 
scarcely  known  and  could  hardly  compete  with  such  bridges  as  were  built  there  of  wood.  This  set  the  inventive  genius  of  the 
western  country  to  work  ; and  some  twenty  or  tw'enty-five  years  ago  several  styles  of  tubular  arch  or  bow'-string  bridges  were  in- 
troduced, at  such  prices  as  to  induce  highway  authorities  to  give  them  a trial : almost  all  these  bridges,  however,  were  built  simply 


4 

t(>  sell,  and  although  the  materials  from  which  they  were  made  were  of  sufficient  size  so  that  they  answered  the  purpose  of  a bridge 
in  most  cases  for  a time,  especially  in  shoi-t  spans:  yet  they  were  generally  constructed  with  so  little  regard  to  the  principles  of  correct 
bridge  construction  that  there  have  been  many  failures  of  these  bridges  and  their  earlier  competitors  and  successors.  About  18G0, 
IMr.  T.  B.  White,  the  founder  of  our  firm,  an  experienced  builder  of  wooden  bridges  of  the  Howe  and  Burr  truss  styles,  on  tlie 
earlier  railroads  (jf  western  Pennsylvania  and  Ohio,  foreseeing  that  iron  was  destined  to  be  the  material  of  which  the  bridge  of  the 
future  was  to  be  built, endeavored  to  elevate  the  standard  of  highway  bridge  construction,  and  introduced  the  Whipple  style  of  bow- 
string bridges,  soon  adapting,  also,  wrought  iron  to  the  arch  meml)ers  of  the  same;  and  there  is  no  doubt  that  these  are  among 
the  best  bridges  now  remaining  of  that  cla.«s  of  structures;  he  also,  knowing  the  acknowledged  pre-eminence  of  the  Howe  truss 
among  wooden  bridges,  attempted  to  introduce  it  in  iron  as  well ; but  it  did  not  prove  to  be  an  economical  design  in  iron  wlien 
compared  to  the  AVhipple  truss  and  was  soon  abandoned,  althougli  a number  of  spans  of  about  one  hundred  feet  each  are  still 
in  j)ei'manent  use  and  mark  the  progress  of  the  science.  It  should  always  be  remembered,  however,  that  the  correct  j)rin- 
ciples  of  bridge  construction  were  but  little  known  or  understood  at  this  time,  and  that  “ rule  of  thumb”  methods  were  the 
rule  and  not  the  exception.  Soon,  however,  influenced,  no  doubt  by  the  fact  that  the  active  minds  of  men  who  had  been  engaged 
in  strife  during  the  late  war,  were  now  diverted  into  ])eaceful  channels,  there  were  immense  strides  taken  in  the  development  of 
correct  mathematical  jrrineijiles  governing  bridge  construction,  not  only  in  general  ])rinciples  but  also  in  those  governing  the 
minutest  details  of  construction  ; and  so  far  has  this  ])rogressed  in  the  past  twelve  or  fifteen  years,  that  it  may  now  lie  said  tliat, 
with  the  majority  of  builders,  more  attention  is  paid  and  more  skill  displayed  than  in  almost  any  other  branch  of  mechanical 
construction  ; and  this  is  the  case,  not  only  in  railroad  bridges,  where  Ave  Avould  naturally  exj^ect  to  see  it,  beeau.se  of  the  intelli- 
gent supervision  of  their  chief  engineers  and  other  officers,  but  competition  has  also  made  it  progress  fully  as  far  in  highway 
bridge  construction.  For  the  benefit  of  those,  however,  who  are  called  ujron  to  have  charge  of  bridge  work  without  the  j)repar- 
ation  or  technical  knowledge  which  belong  to  the  engineering  branch  of  the  j)rofession,  it  may  be  well  to  enunciate  a few  facts 
and  lay  doAvn  a few  sound  principles  which  they  may  follow. 

The  first  thing  to  be  considered  in  the  building  of  a bridge  at  a given  j^oint,  is  the  number  and  length  of  the  6j)ans ; liere  en- 
ter in  the  questions  of  economy  in  first  cost,  and  also  that  of  safety  to  the  Avhole  structure  by  having  the  water  way  so  little  ob- 
structed by  the  number  of  ])iers,  that  there  shall  be  as  little  tendency  as  possible  to  form  ice-gorges,  or  to  affijrd  lodging  jdaces 
for  drift,  which,  by  pounding  or  by  sheer  force  of  their  weight,  and  the  pressure  of  the  v^’ater,  may  endanger  the  masonry. 
All  masonry,  also,  should  be,  where  po.ssible,  of  large  stone,  well  bonded  together  and  thoroughly  united  by  good  cement,  and 
placed  on  a sure  foundation.  Where  such  a sub-structure  is  not  available,  the  fewer  the  number  of  piers  the  better.  To  aid  in 


5 


ascertaining  what  length  of  span  is  the  most  economical,  when  safe,  the  following  statement  may  be  made:  Supposing  tliat  for  a 
long  structure  no  span  less  than  eighty  feet  would  likely  ever  be  adopted;  then  if  such  a s])an,  eighty  feet  long,  would  cost,  sav 
SIS  per  foot;  for  other  spans  the  cost  would  be  about  in  tlie  following  proportion; 

Knowing,  then,  the  amount  of  masonry  rc(piired  for  eacli 
different  number  of  spans  which  may  be  suggested,  the  cost  per 
yard,  and  the  probable  cost  of  foundations,  all  of  which  can  be 
easily  estimated  by  any  one  who  has  ever  had  anything  to  do 
with  charge  of  masonry,  the  most  economical  length  of  span  may  be  figured  out  for  any  locality  by  the  use  of  this  table;  this 
being  determined  upon,  the  width  of  roadway  is  the  next  consideration;  twelve  feet  in  the  clear  between  trusses,  gives  barely 
enough  space  for  the  widest  loads  usually  carried  on  wheels;  and  where  room  for  pedestrians  or  horsemen  to  pass  such  loads  is  de- 
sired, fourteen  or  sixteen  feet  may  be  adopted  for  a single  roadway,  usually  so  termed ; for  a double  roadway,  admitting  the 
passage  of  vehicles  in  opposite  directions,  eighteen  feet  will  answer  for  ordinary,  and  twenty-four  feet  for  the  widest  loads.  For 
sidewalks,  a^  least  four  feet  shouhl  be  allowed  for  the  passage  of  two  persons  in  ojjposite  directions,  and  for  constant  traflic,  from 
six  to  eight  feet  should  be  allowed  that  no  one  may  be  incommoded.  In  cities  or  large  towns,  it  is  often  desirable  (motives  of 
economy  only,  in  general,  preventing)  to  build  bridges  the  full  width  of  the  street:  when  the  location  of  such  bridges  will  allow 
of  their  being  of  the  deck  pattern  it  will  usually  be  found  economical  that  the  trusses  should  be  placed  from  sixteen  to  twenty 
feet  apart,  with  overhanging  sidewalks.  Another  point  should  be  considered  in  fixing  the  width  of  roadways,  namely,  the  lateral 
stifihess;  for  although  bridges  may  be  made  sufficiently  strong  to  re.<ist  any  wind  pressure,  having  long  sj)an  and  narrow  nnul- 
ways;  yet  for  this  consideration  we  should  advise  that  bridges  of  ditierent  lengths  of  span  should  have  roailways  not  less  than 
given  in  accompanying  table. 

Next  comes  the  determination  of  the  strength  re<purod.  As  a general  rule  bridges  which  are  not 
likely  to  be  subjected  to  frecpient  heavy  loading  may  be  lighter  than  those  subjected  to  constant  or 
even  frequent  crossing;  and  bridges,  which,  by  reason  of  constant  crossing,  are  likely  to  be  at  times 
nearly,  or  (juite  cov’ered  with  loaded  vehicles  or  large  droves  of  cattle,  should  be  rccpiired  to  be 
stronger  than  those  which  are  never  likely  to  have  more  than  a few  head  of  cattle  or  two  oi-  three 
teams  on  them  at  any  one  time.  For  these  and  like  reasons  we  have  made  the  divisions  into  classes  which  are  shown  in  the  table 
of  required  strength  on  the  seventh  page.  The  use  of  this  table,  it  should  be  remembered,  must  be  governed  by  the  judgment 
of  the  person  using  it.  Local  conditions  might  require  for  instance,  that  a bridge,  which  the  heading  of  the  first-class  would 


Span. 

Hoadway. 

up  to  loO' 

12  feet. 

140  to  200' 

14  “ 

200  to  250' 

1()  “ 

250  to  300' 

1<S  “ 

Span. 

Cost  per 
Lineal  Foot. 

Span. 

Cost  per 
Lineal  Foot. 

Span. 

Cost  per 
Lineal  Foot. 

30  feet. 
100  “ 
.120  “ 

SLS.OO 

20.00 

22.50 

140  feet. 
IfiO  “ 
180  “ 

S25.00 

28.00 

31.00 

200  feet. 
225  “ 
250  “ 

635.00 

37.50 

40.00 

6 

2)roperly  describe,  should  be  made  of  tlie  strength  given  under  the  second,  or  even  third  class.  We  only  mean  to  give  a basis 
which  may  be  assumed  as  the  minimum  strength  which  should  be  required  for  bridges  of  certain  g^ieral  classes. 

There  are  certain  points  in  most  bridges  which  are  subjected  to  larger  concentrated  loads  than  those  given  by  the  table 
would  indicate;  these  are,  the  Hoor  system — joist,  beams  and  beam  hangers,  vertical  suspenders,  counter  bracing  and  center 
jDOsts;  all  these  should  be  proportioned  for  as  heavy  a concentrated  or  local  load  as  can  be  ascertained  as  used  or  likely  to  be 
used  in  the  vicinity.  Among  the  heaviest  pieces  of  machinery  likely  to  be  taken  over  any  bridge  are  the  road  engines  in  use  in 
some  parts  of  the  country,  which  have  a weight  of  eight  tons  on  a wheel  base  of  about  eight  feet  by  five.  On  roads  where  circuses 
pass  the  weight  of  the  largest  elephant  may  be  a point  to  be  taken  into  consideration;  their  weights  should  be  taken — with  al- 
lowance for  impact — at  six  tons;  the  distance  between  the  fore  and  hind  feet  being  al)Out  eight  feet,  from  which  the  load  on  any 
beam  may  be  determined,  and  the  proportion  of  the  load  may  safely  be  assumed  as  in  the  exact  center  of  beam  or  roadwa)'. 

For  bridges  in  cities  where  Aveling  & Porter  steam  road  rollers  are  used,  their  concentrated  weight  should  be  provided  for: 
the  weight  on  front  axles  is  about  14,000  tbs.  in  a width  of  fifty  inches;  the  hind  axle  (the  axles  are  about  eleven  feet  on  centers) 
supports  a weight  of  22,000  fts.;  wheels  six  feet,  center  to  center. 

In  addition  there  may  be  a few  points  mentioned  which  should  also  be  borne  in  mind  as  important  ones  in  the  selection  and 
construction  of  a bridge. 

1st.  The  greater  the  capacity  and  conseejuent  dead  load  of  the  bridge,  the  less  will  be  the  effect  j)roduced  on  it  by  a rap- 
idly moving  load.  In  other  words,  a heavy  bridge  is  stiffer  than  a light  one. 

2nd.  It  is  important  that  all  parts  should  be  properly  proportioned  to  meet  the  exact  strains  calculated  to  come  upon  tliem ; 
for  even  if  one  or  more  members  may  have  for  example  ten  per  cent,  excess  of  material  over  that  required,  yet  if  any  one  mem- 
ber has  a deficiency  of  five  per  cent.,  the  whole  bridge  might  as  well  be  deficient  five  per  cent,  as  far  as  the  carrying  power  is 
concerned.  A bridge  is  no  stronger  than  its  weakest  member. 

3rd.  The  quality  of  the  iron  should  be  well  looked  after.  A good  bridge  iron  will  stand  from  45,000  to  50,000  lbs.  per 
square  inch  ultimate  strength;  21,000  to  20,000  lbs.  elastic  limit;  and  will  have  a good  fiber  and  can  be  bent  cold  from  90°  to 
180°  without  fracture. 

4th.  The  details;  as  the  riveted  connections,  the  bearings  of  pins,  rivets  and  stirrups;  the  size  of  the  pins  as  determined  in 
relation  to  their  greatest  bending  moment,  the  lateral  connections,  the  proper  painting  of  the  iron  and  protection  of  machined 
surfaces  before  erection,  are  all  points  which  can  only  be  secured  by  the  minutest  specifications  and  the  constant  care  of  an  expert 
inspector,  or  else  by  the  sedulous  care  of  a company  which  exercises  a jealous  regard  of  its  own  reputation. 


7 

5th.  It  is  often  the  case  that  proper  care  is  not  taken  of  bridges  after  erection  ; they  should  be  examined  occasionally  to  see 
that  dirt  has  not  accumulated  around  the  ends  of  trusses:  -where  there  are  any  nuts  in  use  they  should  be  kej)t  tight,  and  the  iron 
work  painted  sufficiently  often  to  prevent  rust. 


Table  Showing  Live  Load  in  Pounds  per  Square  Fool  of  Roadway. 


I>ENGTII 

OF 

Scans. 

! Couiury  Bri<lges 

not  on  Main  Roads. 

Bridges  in  Towns, 

or  Principal  Roads  in  Country  Between  Towns 

Bridges  in  Large  Towns  or  Cities. 

Bridges  on  Main  Streets 

1 in  Largest  Cities. 

Roadway. 

Roadway. 

Roadway. 

j Any  Roadway. 

12^ 

14' 

16' 

18' 

12' 

14' 

16' 

18' 

20' 

22' 

24' 

16' 

18' 

20' 

24' 

30' 

40' 

60' 

Under  6o' 

100 

TOO 

TOO 

TOO 

125 

125 

I TO 

1 10 

I 00 

TOO 

TOO 

150 

150 

150 

150 

125 

125 

’25 

’5° 

6o'  to  xoo' 

TOO 

TOO 

90 

90 

T TO 

r TO 

TOO 

TOO 

TOO 

90 

90 

125 

'25 

125 

•25 

>25 

TOO 

I 00 

'5° 

o 

c 

TOO 

90 

80 

80 

TOO 

TOO 

TOO 

90 

90 

«5 

125 

125 

125 

125 

•25 

TOO 

TOO 

I 23 

125  to  150 

90 

S5 

75 

75 

TOO 

100 

90 

80 

80 

75 

75 

125 

125 

125 

I TO 

1 10 

TOO 

90 

'25 

150'  to  175' 

, 85 

80 

75 

70 

90 

80 

75 

75 

70 

65 

I TO 

I TO 

I TO 

I 00 

TOO 

90 

80 

-25 

I 75' to  200' 

75 

70 

65 

75 

70 

70 

65 

60 

T 10 

I TO 

TOO 

90 

80 

80 

' 25 

200'  to  250' 

60 

55 

65 

65 

60 

55 

TOO 

90 

80 

70 

70 

1 I 00 

250'  to  300' 

50 

55 

50 

45 

45 

80 

80 

70 

60 

60 

i too 

Over  300' 

1 

45 

40 

40 

70 

60 

50 

50 

1 00 

With  these  loads  the  proper  allowable  strains  on  iron  are:  For  princi])al  tension  members:  12,500  lbs.  p(‘r  sipuire  inch  ; 
counters  and  suspenders — 10,000  lbs.  per  stjuare  inch  ; floor  beam  hangers — 9,000  lbs.  ])er  sipiare  inch  ; comj)rcssion  meml)ers — 
10,000  lbs.  per  scjuare  inch  ; reduced  by  Gordon’s  or  Rankin’s  formulas.  The  load  on  sidewalks  may  be  taken  from  40  to  100  lbs. 
per  square  foot,  according  to  amount  of  travel. 


8 


I 


BRIDGE  IN  BERKS  CO..  PA. .-200  Foot  Span.  18  Foot  Roadway. 

BUILT  BY  THE  PENN  BRIBLE  CD. 


THREE  QEARTER  DECK  liRllXiE,  HEAVER  EAELS,  1*A. 


Four  Spans.  1 55  Feet  Each.  20  Foot  Roadway 

BUILT  BY  THE  PENN  BRIDLE  CD, 


10 

DOUBLE  INTERSECTION,  WHIPPLE  OR  LINVILLE  TRUSS  BRIDGES. 

Ou  page  8 is  a good  illustration  of  a Doulile  Intersection,  Whipple 

or  Linville  Truss  Bridge.  These  bridges  we  erect  for 

spans  of  140  feet  and  over.  In  addition  to  the  span  shown 

we  would  mention  the  following 

as  a few  of  the  many  of  this  type 

which  we  hav'e  built. 

Baltimore  County,  ^laryland. 

One  Span, 

205  feet: 

roadway. 

20  feet. 

Frederick  County,  ^Maryland. 

One  “ 

125  “ 

H 

14  “ 

New  Brighton,  Pennsylvania. 

Two  Spans, 

200  “ 

H 

20  “ and  one  5 foot  walk. 

Franklin  County,  Pennsylvania. 

One  Sjmn, 

120  “ 

n 

10  “ 

Allegheny  County,  Pennsylvania. 

One  “ 

125  “ 

a 

17  “ 

Warren  County,  Chio. 

Two  “ 

150  “ 

n 

10  “ 

Sandusky  County,  Ohio. 

One  Span, 

140  “ 

n 

18  “ 

Lake  County,  Ohio. 

One  “ 

100  “ 

10  “ 

Fayette  County,  Ohio. 

One  “ 

no  “ 

(( 

18  “ 

Lawrence  County,  Ohio. 

One  “ 

132  “ 

u 

10  “ 

Essex  County,  New  York. 

( )ne  “ 

150  “ 

n 

14  “ 

Panola  County,  Mississippi. 

One  “ 

160  “ 

<( 

10  “ 

Kewaskuiu,  Wisconsin. 

One  “ 

130  “ 

n 

10  “ 

Galt,  Illinois. 

Two  Spans, 

140  “ 

n 

10  “ 

Tyler  County,  West  Virginia. 

One  “ 

140  “ 

n 

10  “ 

Culpepper  and  Fauquier  Cos.,  Va. 

One  “ 

150  “ 

il 

12  “ 

On  page  9 is  shown  a peculiar  type  of  bridge,  styled  three  quarter 

deck,  the 

floor  being  raised  in  the  truss,  or  rather  the 

truss  put  mostly  below  floor  for  the  purpose  of  saving  masonry. 

SINGLE  INTERSECTION,  WHIPPLE  OR  PRATT  HIGH  TRUSS. 


11 


liridges  are 


The  cuts  ou  opposite  pages  12  and  13  represent  Single  Intersection,  'Whipple  or  Pratt  High  Trusses.  These 
adapted  to  spans  of  from  eighty  to  two  hundred  feet,  and  are  likely  used  more  than  any  other  style  of  Truss.  In  addition  to 
the  bridges  at  the  locations  shown  in  the  engravings,  we  would  name  the  following  points  as  a portion  of  the  many  where  we  have 
erected  this  style : 


City  of  IMilwaukee,  Wis. 

La  Valle,  Wisconsin. 

Two  Rivers,  Wisconsin. 

Butler  County,  Iowa. 

Peru,  Illinois. 

Wayne  County,  Indiana. 

Grenada,  Mississippi. 

Flint,  Michigan. 

Eagle,  Michigan. 

Conway,  Massachusetts. 

Limestone  County,  Alabama. 

Mercer  County,  New  Jersey. 

Frederick  County,  Maryland. 

Cecil  County,  Maryland. 

Tyler  County,  West  Virginia. 

Giles  County,  Tenn. 

Collins  County,  Texas. 

Sherman,  Texas. 

Co'bke  County,  Texas. 

Travis  County,  Texas. 

Cleveland  County,  North  Carolina. 

Mason  and  Cabell  Counties,  West  Virginia. 


Erie  County,  New  York. 

Chatauqua  County,  New  York. 

Red  House,  New  York. 

Newburgh,  New  York. 

Columbiana  County,  Ohio. 

Lawrence  County,  Ohio. 

Butler  County,  Ohio. 

Pickaway  County,  Ohio. 

Jeherson  County,  Ohio. 

IMiarni  County,  Ohio. 

Carroll  County,  Ohio. 

IMercer  County,  Pennsylvania. 
Washington  County,  Pennsylvania. 
Westmoreland  County,  Pennsylvania. 
Montgomery  County,  Pennsylvania. 
Lawrence  County,  Pennsylvania. 
Luzerne  County,  Pennsylvania. 
Butler  County,  Pennsylvania. 

Elk  County,  Pennsylvania. 

Bridgewater,  Penn’a,  | ^ 200^ 


160'  t 


Treichler’s,  Lehigh  County,  Pennsylvania. 


20  ft.  Roadway  and  one 
5 ft.  walk. 


12 


BRIDGE  AT  SMITH'S  FERRY.  PA.— Span  of  238  Feet.  16  Foot  Roadway. 

BUILT  BY  THE  PENN  BBTDG-E  CD. 


13 


BRIDGE  AT  NEW  GALILEE.  PENN.-130  Foot  Span.  16  Foot  Roadway 

BUILT  BY  THE  PENN  BRI i EE  CD, 


DETAILS  OF  HIGH  TRUSS  BRIDGES. 


I At  A and  B are  sliown  ditfercnt  designs  of  hip  connections  for  high  truss  bridges,  and  are  both  good  details ; that  at  A 

! however,  giving  the  nearest  approach  we  think  practicable  to  a scpiare  or  tlat  bearing.  At  C and  E are  elevations  of  shoes ; 

I that  at  E is  the  more  usual,  while  that  at  C gives  probably  a more  evenly  distributed  pressure  of  the  shoe  on  the  masonry.  We 

have  shown  on  the  cross  section  of  shoe  at  D,  a stiff  lateral  connection  made  of  angle  bar;  while  that  at  F shows  the  ordinary 
'i  adjustable  lateral  connection  made  of  round  iron  with  a flattened  eye;  the  detail  shown  on  elevation  of  connection  of  the  lateral 

to  shoe  is  also  used  on  U2)i)er  chord  and  floor  beams ; other  lateral  connections  for  upper  chord  are  shown  in  the  sections  at 

G,  and  Q,  and  for  beams  at  H,  P and  R.  Beams  are  shown  above  the  chord  at  H,  and  suspended  at  P and  R.  The  posts, 

, we  almost  always  use  of  two  channel  bars  latticed  as  shown  in  section  at  O;  and  details  in  connection  with  side  view  of  ujijier 

I chord  made  of  built  channel  at  I;  side  elevation  of  post,  at  center,  for  double  intersection  bridge  at  K,  and  side  view  of  lower 

chord  at  L:  also  in  connection  with  cross  section  of  upper  chord  at  G,  and  (^;  and  cross  sections  of  lower  chord  at  H,  P and 

R.  Knee  braces  are  shown  at  intermediate  posts  in  details  I and  ]\I.  End  elevations  with  portal  bracing  and  cross  .sections 
with  and  without  lower  struts,  diflering  for  different  heights  of  tfuss  are  shown  at  T and  l^. 


I 

I 


PEW  BKIIXJE  CO.,  BEAVEK  FALLS,  PA. 


SIDE  ELEVATION  OF  LOW  TRUSS  BRIDGES. 


On  page  16  are  represented  several  styles  of  low  truss  bridges  of  our  manufacture.  Tlie  first  is  tlie  ordinary  Whipi)le 
Truss;  these  we  built  with  Latticed  Suspenders,  to  aid  in  bracing  the  Truss  sidewi.se;  the  second  is  a modification  of  the  first  in 
the  inclination  of  the  End  Post;  the  third  is  the  Warren  Truss,  and  is  a very  economical  construction  for  Low  Truss  Bridges, 
and  as  we  have  made  them,  have  given  veiy  great  satisfaction.  The  inclination  of  the  end  post,  it  will  be  noticed,  is  about  the 
same  as  in  the  second  style  usually  termed  “Low  Truss”  with  half  battered  End  Post.  Of  the  Hub  Plank  or  (luard,  we  show 
three  styles?,  viz;.  Plank,  Iron  Lattice  and  Gas  Pipe;  either  of  these  can  be  used  on  any  style  of  tru.ss,  according  to  choice  and  cost. 

We  have  Low  Truss  Bridges  in  considerable  numbers  in  almost  every  State  east  of  the  Missouri  River. 


DETAILS  OF  LOW  TRUSS  BRIDGES,  SHOWN  ON  PAGE  17. 

♦♦♦ 

At  A,  is  shown  detail  of  construction  at  hi])  of  middle  or  lower  style  of  bridge  on  page  Hi.  At  B is  the  detail  of  similar 
connection  in  the  first  style  on  same  page.  I and  K rej)resent  the  Shoe  of  any  of  these  Bridges.  C and  L shows  side  elevation, 
and  I)  and  M Cross  Section  at  same  point  for  a Low  Whipijle  Truss  with  suspended  built  floor  beam  and  channel  iron  post;  at 
S is  shown  an  isometrical  view  of  the  same  lower  chord  connection  for  bridge  with  sidewalk  and  handrail ; at  R the  same,  with 
solid  rolled  I floor  beam  and  joists. 

At  E and  N are  shown  side  elevations,  and  at  E and  O cross  sections  at  the  same  j)oints  of  upper  and  lower  chords  of  a low, 
Whipple  Truss  Bridge,  with  angle  iron  posts,  and  built  beam  placed  above  lower  chord ; an  isometrical  view  of  same  is  shown  at  Q. 

G,  H and  P show  similar  details  of  the  Warren  Truss. 


BRIDGE  AT  CITY  OF  RAHWAY,  NEW  JERSEY. 


On  page  ‘20  is  an  extreme  case  of  a low  truss  l)ri(lge,  erected  by  us  in  the  City  of  Uahway,  New  Jersey.  The  span  is  110 
feet  with  one  roadway  36  feet  wide  in  the  clear,  and  two  sidewalks  each  10  feet  wide  in  the  clear,  being  the  longest  span  and 
widest  single  roadway  of  any  low  truss  which  we  know  of  having  been  built. 

On  page  21  is  shown  an  ordinary  low  truss  bridge  of  nO  feet  span. 


MONROE  STREET  BRIDGE. — Built  by  the  Penn  Bridge  Co 


21 


BRIDGE  AT  PEEKSKILL,  N Y.-Span  53  Feet.  14  Foot  Roadway 
BUILT  BY  THE  PENN  BRIE  EE  CD, 


22 


ri:\.\'  Hiiiixn:  co.,  heavp:k  falls,  fa. 


J 


-\ 

23 


DRAW  BRIDGES. 


In  draw  bridges,  is  required  the  most  accurate  workmanship  of  any  class  of  l)ridge  work,  as,  in  addition  to  their  being  re- 
quired to  sustain  loads  under  different  conditions,  ease  in  turning  the  bridge  can  only  be  maintained  by  having  insured  good 
work  when  the  bridge  is  new.  In  addition  to  the  style  shown,  we  also  manufacture  almost  all  styles  of  trusses,  both  high  and 
low,  with  parallel  chords,  for  the  same  purpose. 

We  would  name  the  following  draw-bridges  as  having  been  lately  built  by  us. 

Span,  140  feet;  18  feet  roadway  and  two  5 feet  sidewalks:  Milwaukee,  Wisconsin. 

“ lot)  “ 18  “ “ “ two  7 “ “ Milwaukee,  Wisconsin. 

“ 120  “ 22  “ “ “ two  f)  “ “ Railway,  New  Jersey. 

“ 120  “ 12  “ “ Noxubee  County,  l\li.ssissipjii. 

“ 100  “ 1()  “ ‘‘  Shebovgan,  Wi.sconsin. 


24 


SUSPENSION  BRIDGE  AT  FRANKLIN.  OHIO.— Single  Span  of  365  Feet.  20  Foot  Roadway 

BUILT  BY  J.  W,  SHIPMAN,  ENBINEER, 


SUSPENSION  BRIDGES, 


(^f  which  an  excellent  example  is  shown  on  the  op])osite  {tage,  are  best  adajjted  of  any  style  for  long  spans;  say  from  300 
to  1000  feet.  When  properly  constructed  these  bridges  cannot  be  excelled,  and  have  stood  the  test  of  long-continued  use.  Their 
economy  in  cost  is  greatest,  when,  for  shorter  spans,  it  would  recpiire  numerous  and  expensive  foundations.  This  department  is 
in  charge  of  ourPIastern  agent,  J.  W.  Shiimian,  C.  E.,  who  has  devoted  to  it  many  years  of  study.  The  following  successful 
examples,  of  his  construction,  attest  the  value  of  his  experience  : 


Bridge  at  Harrison,  Ohio. 

“ “ Linwood,  Ohio. 

“ “ Turner’s  Falls,  Mass. 

Foot  “ “ Delaware,  Ohio. 

“ “ Charleston,  W.  Va. 

“ “ Windsor  Locks,  Conn. 


Single  Span  of  420  feet  by  18  foot  roadway. 

“ “ “ ddO  “ “ 20  “ 

“ “ “ o^{)  “ “ “20  “ 

“ “ “ “200  “ “ (5  “ 

“ “ “ 2S0  “ “18  “ 

Center  Span  of  550  feet  and  two  approach  s])ans  ol’  300  feet  each, 
by  20  foot  roadway. 


26 


TUBULAR  PILRS 

— riLLElO  WITH  — 

PILES  <5  concrete: 


V 


IRON  SUB-STRUCTURES. 

We  are  jtrepared  to  build  any  kind  of  iron  sub-strnctnre^  in  localities  where  masonry  is  not  available,  or  where  tlnyv  can 
be  built  nuich  cheaper  than  stone  work. 

The  styles  most  commonly  used  by  us  are  shown  on  opposite  page. 


2y  . COLUMBIA  UNIVEPCirf  " ‘ ^ “ [ 

In  additiun  to  the  styles  of  trusses  illustratetl  in  this  painpldet,  we  are  prepared  to  build  all  styles  of  Deck  Arches,  Canti-  I 
levers,  and  all  styles  of  Trusses  having  upper  chords  more  or  less  inclined. 

\>'e  also  build  Combination  Bridges  with  u])pir  chords  and  posts  of  wood;  or  with  wooden  chords  and  iron  posts;  the  details  ! 
of  these  bridges  are  made  hrst-class  in  every  particular.  At  the  date  of  issuing  this  catalogue,  however,  the  price  of  all  iron 
bridges  is  so  low  that  but  very  few  combination  bridges  are  called  for. 

W e trust  that  no  one  at  the  present  day  is  deterred  frotn  building  iron  bridges  in  the  place  of  wood  by  the  difference  in  the  cost, 
as  it  is  now  very  slight  for  bridges  of  equal  cajiacity;  and  with  the  growing  scarcity  of  timber,  it  is  likely  by  the  time  a wooden 
bridge  would  l)e  worn  out  that  it  could  not  be  rejilaced  with  wood  for  any  less  than  iron.  Therefore,  build  iron  now.  We  are  i 

glad  to  quote  jirices  at  any  time.  In  writing  for  prices,  please  give  us  as  much  of  the  following  information  as  possible:  nuin-  j 

her  and  length  of  sj)ans ; width  of  roadways  and  number  and  width  of  foot  walks;  name  of  nearest  Railroad  Station  and  its 
distance  from  bridge  site;  depth  of  water  at  low  and  high  stages,  and  height  of  flcjor  above  water;  what  class  the  bridge  would  I 

come  under  in  our  table,  and  whether  in  your  judgment  any  stronger  bridge  is  reijuired. 

The  Penn  Bridge  Works  were  first  established  in  in  a small  way,  and  have  grown  since — so  that  in  the  past  three 

years  the  amount  of  work  turned  out  amounted  to  20,000  lineal  feet  of  single  track  iron  bridges.  The  total  amount  built  by 
these  works  since  their  start  will  amount  to  over  ten  miles.  I 

Two  main  lines  of  railroads  (on  which  we  have  our  own  siding)  passthrough  our  town,  the  I’ittsburgh,  Ft.  Wayne  A Chicago 
Railroad  (Pennsylvania  system)  and  the  Jbttsburgh  A Lake  Erie  Railroad  (Vanderbilt  system;.  Our  works  are  easily  accessi- 
ble to  visitors,  whom  we  always  welcome  and  are  glad  to  show  through  our  establishment  and  over  several  fine  bridges  in  the 
immediate  vicinity;  they  are  also  admirably  situated  for  convenient  access  to  the  principal  iron  markets  of  the  country,  and 
having  natural  gas  and  other  special  advantages  for  manufacturing  and  shipping  to  all  points;  in  addition  to  the  railroads 
named,  the  Ohio  River  being  only  three  miles  distant. 

Among  other  manufactories  of  the  Beaver  Valley,  lying  within  a range  of  five  miles  uji  and  down  the  river,  are  large  Iron, 
Steel,  Wire,  Rivet,  Cutlery,  File,  Axe  and  Saw  Works,  several  Glass  Works  of  various  branches,  and  numerous  Potteries  and  ! 
Brick  Works.  j 

We  hope  to  hear  from  you  when  you  have  any  bridges  to  let  or  in  contemplation,  and  all  business  intrusted  to  us  will  have 
prompt  and  careful  attention. 

Re-sj)ectJ'ully, 

PENN  BRIDGE  CO.  . 


1 


V.- 


» .<1 


I' 

if 


1 


h‘ 


1 


1 

V 


i 


BRIDGE  AT  FLIXT,  MICHIGAN. 

Span  of  130  Feet.  Two  16  Ft.  Pvoadways.  Two  8 Ft.  Sidewalks. 


